Medlen (5-7) limited the Royals to a run in the first and Eric Hosmer's two-run homer in the fifth while striking out five. He turned the game over to Jordan Walden, who survived a leadoff walk in the eighth inning to get the game into the hands of Craig Kimbrel.

The Braves closer walked Mike Moustakas and gave up a single to David Lough to start the ninth, but rallied to strike out Elliot Johnson and Jarrod Dyson. Kimbrel intentionally walked Alex Gordon to load the bases, and then got Alcides Escobar to fly out to right on the first pitch.

The escape job was Kimbrel's 22nd save.

Heyward drove in a pair of runs with a double in the fifth, and then broke open a tied game with his solo shot off Tim Collins (2-2) with one out in the seventh inning.

In a curious twist to interleague play, the Royals had played 142 games against NL teams at Kauffman Stadium without a visit by Atlanta. If not for last year's All-Star Game at the K, longtime Braves third baseman Chipper Jones would have retired having never played in the park.

The opener of the two-game set was dominated by stingy pitching.

The Royals scratched out their first run off Medlen in the first when Alex Gordon reached on a single, took second on an error and went to third on a sacrifice bunt. But he was caught in a rundown on a grounder by Hosmer, who reached second before Gordon was tagged out.

Hosmer scored on Billy Butler's ensuing single.

That was all the Royals would muster off Medlen until Escobar managed a two-out single in the fifth. The resurgent Hosmer followed with his tying two-run shot over the right-field wall, his fourth home run of the season but third in 10 games.

It proved to be timely, too, coming just after the Braves pulled ahead.

Santana had struck out five through the first three innings, but began running into trouble the second time through the Braves' power-packed lineup. But it wasn't home runs that gave them the lead, but a series of singles and doubles.

Chris Johnson led off the fifth with a double, and Andrelton Simmons put runners on the corners with his base hit. Jordan Schafer tied the game 1-all on his double, and Heyward's double down the right-field line gave the Braves a 3-1 lead.

Heyward didn't hit that ball particularly hard. The one he hit off Collins in the seventh was crushed.

Heyward greeted a 0-2 pitch from the Royals' diminutive left-hander with a ferocious swing that sent the ball soaring over the wall in right field and gave the Braves a 4-3 lead.

The Braves began the day with 96 homers, tied with Colorado for first in the National League. Heyward's sixth of the season allowed the Braves to improve to 41-9 in games in which they homer. They are 4-23 in games without a home run.

Notes: Braves OF Justin Upton was the DH after missing two games with a sore right hand. ... The Royals recalled LHP Will Smith and optioned RHP Kelvin Herrera to Triple-A Omaha. They also reinstated LHP Danny Duffy (Tommy John surgery) from the 60-day DL and optioned him to Omaha, where he worked five scoreless innings Tuesday night. ... LHP Mike Minor pitches for the Braves in the finale of the two-game set. RHP Luis Mendoza goes for the Royals on Wednesday night.